Re: GPL and other licences

[Graham Murray]

Stefaan A Eeckels <hoendech@ecc.lu> writes:

> Only in the very specific case of programs that normally read commands
> interactively, and if they have been modified ("If the _modified_
> program _normally reads commands interactively_"). The beginning of the
> clause is very specific, so you're straining it by claiming that it
> applies to all GPLed works. It's not even all interactive programs, it's
> programs that read commands interactively. 

Agreed. However it must not be forgotten that when the GPL was written
(and this same clause is also in version 1) most interactive computing
was done on multi-user systems via terminals. Therefore it was very
likely that the user (to whom the notice has to be displayed) was not
the owner of the copy of the software which they were running. This
clause requires that users (of a modified program which reads commands
interactively) be told that they *do* have the right to redistribute
the program under the conditions of the GPL. This implies that the GPL
requires that licensee of such programs must either permit users to
make copies themselves or provide copies to users on request.

I doubt that the intention was to provide more rights to users of
modified programs which read commands interactively than to users of
any other software licensed under the GPL. Therefore by extrapolation
it is saying that by licensing the work under the GPL (which is
required when an original work is modified) the licensee (for the
moment take that to be the owner of the physical copy) must permit
users of the work to obtain copies (and thus become licensees
themselves) which they are then free to distribute and/or modify under
the terms of the GPL.